Knowing, that the threshold voltage of the EEPROM memory cells is a key parameter to determine the overall performance of the memory, a build in structure to extract this information is a very relevant choice to fast diagnose failure in the memory. Thus, the objective of this paper is to present a built in self-diagnosis of EEPROM memory cells, based on threshold voltage extraction. In order to extract the threshold voltage, the modified circuit and the associated test sequence are presented. Based on the threshold voltage extraction, complementary information is proposed to improve the classical memory diagnosis methodology.